Psychology as an experimental science or Scientific Psychology began in 1879 in Leipzig, Germany.
Wilhelm Wundt studied Medicine at the University of Heidelberg and founded the first psychological laboratory to examine conscious experience in 1879. For what is considered to be the date, place and author who introduced the scientific method applied to human behavior.
La Psicología como ciencia experimental o Psicología Científica empezó en 1879 en Leipzig, Alemania.
Wilhelm Wundt estudió Medicina en la Universidad de Heidelberg y fundó el primer laboratorio psicológico para examinar la experiencia consciente en 1879. Por lo que se considera que es la fecha, sitio y el autor que introdujo el método científico aplicado a la conducta humana.
Experimental psychology refers to work done by those who apply experimental methods to psychological study and the processes that underlie it. Experimental psychologists employ human participants and animal subjects to study a great many topics, including (among others) sensation & perception, memory, cognition, learning, motivation, emotion; developmental processes, social psychology, and the neural substrates of all of these.
Wilhelm Wundt
Main article: Wilhelm Wundt
Experimental psychology emerged as a modern academic discipline in the 19th century when Wilhelm Wundt introduced a mathematical and experimental approach to the field. Wundt founded the first psychology laboratory in Leipzig, Germany.[2] Other experimental psychologists, including Hermann Ebbinghaus and Edward Titchener, included introspection among their experimental methods.
Charles Bell
Main article: Charles Bell
Charles Bell was a British physiologist, whose main contribution was research involving nerves. He wrote a pamphlet summarizing his research on rabbits. His research concluded that sensory nerves enter at the posterior (dorsal) roots of the spinal cord and motor nerves emerge from the anterior (ventral) roots of the spinal cord. Eleven years later, a French physiologist Francois Magendie published the same findings without being aware of Bell’s research. Due to Bell not publishing his research, the discovery was called the Bell-Magendie law. Bell’s discovery disproved the belief that nerves transmitted either vibrations or spirits.
In its early years, consumer behaviour was heavily influenced by motivation research, which had increased the understanding of customers, and had been used extensively by consultants in the advertising industry and also within the discipline of psychology in the 1920s, '30s and '40s. By the 1950s, marketing began to adopt techniques used by motivation researchers including depth interviews, projective techniques, thematic apperception tests and a range of qualitative and quantitative research methods.
When Most of scholars on this thread are unanimous that Experimental Psychology emerged as a modern academic discipline in the 19th century when Wilhelm Wundt introduced a mathematical and experimental approach to the field. Wundt founded the first psychology laboratory in Leipzig, Germany. For details consult:
Boring, Edwin G. (2008): History of Experimental Psychology (Two Volumes), New Delhi: Cosmo Publications
Carl Jung Was founder of Analytical Psychology and Sigmund Freud in has developed Psychoanalysis. Wilhelm Wundt is rightly considered introducer of experimental psychology.
I think, there is no need of further discussion about who developed experimental psychology.